CVE-2026-64073

Last refreshed2026-10-17

Status: UPDATED | Advisory ID: CVE-2026-64073

Key Details

CVE	CVE-2026-64073
CVSS Score / Version	7.8 (High) / CVSS v3.1
Updated	2026-10-16
CVSS Vector	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`
CVSS Prose	attack vector is local; attack complexity is low; privileges required is low; user interaction is none; scope is unchanged; confidentiality impact is high; integrity impact is high; availability impact is high.
Affected products	Linux Kernel
Classified as	CWE-416 (Use After Free)

Vendor	Product	Affected Versions	Patch Status
Linux	Linux Kernel

Vendor

Product

Affected Versions

Patch Status

Linux

Linux Kernel

Subsystems	OT Supporting Infrastructure
Sectors	All Sectors

In the Linux kernel, the following vulnerability has been resolved:

irq_work: Fix use-after-free in irq_work_single() on PREEMPT_RT

On PREEMPT_RT, non-HARD irq_work runs in per-CPU kthreads via

run_irq_workd(), so irq_work_sync() uses rcuwait() to wait for BUSY==0.

After irq_work_single() clears BUSY via atomic_cmpxchg(), it still

dereferences @work for irq_work_is_hard() and rcuwait_wake_up().

An irq_work_sync() caller on another CPU that enters after BUSY is cleared

can observe BUSY==0 immediately, return, and free the work before those

accesses complete — causing a use-after-free.

Fix this by wrapping run_irq_workd() in guard(rcu)() so that the entire

irq_work_single() execution is within an RCU read-side critical

section. Then add synchronize_rcu() in irq_work_sync() after

rcuwait_wait_event() to ensure the caller waits for the RCU grace period

before returning, preventing premature frees. (NVD)

Monitor Linux's web page for any future patch releases.

Source	Reference
NVD	https://nvd.nist.gov/vuln/detail/CVE-2026-64073
CVE	https://www.cve.org/CVERecord?id=CVE-2026-64073

Source

Reference

NVD

CVE